Loop aerial



Apfil 22, 1930. A, G', HARMs 1,755,820

LOOP AERIAL Filed DeC. 24, 1925 40 ing means, and

Patented Apr. 22, i936@ Loor AERIAL Application filed vIDemamber 24,1925. lSerial No. 77,568.

Y. This invention relates to a loop aerial or antenna for collectingradio or electric waves or energy, asfor a lradio broadcast receiver.

:Among the objects ofthe. invention are to y provide anovel winding andconstruction of inside or loop aerialV in the form of a completeenclosure or closed loop,l the-winding or coils of which are ofcontinuous form with no largegaps throughout the surrounding sidesarea,or field, or which may be stated as havinggan'area about which the wiresare wound to wholly enclose said area, which is smaller and morecompact, as well as easier to manipulate than loop aerials heretoforeproduced, and which has `greater linductance than other loops of thesame size and better directional effect. l K It is also an'ob] ect ofthe invention to provide a novel form of loop aerial which includes aframe of novel construction enclosed by a winding o n all sides, vtheframe being such that the winding. of the aerial is simplified andquantity production is facilitated.

Other objects and advantages will be ap- 25 parent as the descriptionproceeds.

' In the accompaning drawings J Fig. `1 is a top plan view of my novelloop aerial. v d F ig.2 is a side elevation of the device.

Figs. 3 and 4 are transverse, horizontal, sectional yviews taken on thesection lines 3-3 and 4 4 of Fig. 2 and looking in the directionsindicated'fby the arrows.

Figs. 5, 6, 7,1and8 are kplan views' of modifications showing differentgeometrical shapes. I

Fig. 9 is a fragmentary detail elevation showing wire-mounting means forthe coil.

Fig. 10 is a similar view of another mountnr Fig. llis a detailtransverse, sectional view taken on the section line 11-11 of Fig. 10.

Referring to the drawings in detail, and

. especially ytoFigs. 1 to 4 inclusive, my novel 45 aerial is shown ascomprising a frame including abase 12 havingfa soft covering 13V ofcloth, felt, or rubber, yon the bottom Ato prevent noise .and marringo`r` scratching the surface of a table, console, or other cabinet orsupport upon which the device isusually re-V yposed when in use and tokeep the base stationary. 1 f v Extending up from the center of the base12 is a pivot pin or post 14, around which and mounted upon the base soas to be rigid there-v with, may be disposeda raised circular contact orbearing plate or disk 15 preferablyof `Bakelite or other insulationhaving a cen'- tral aperture receiving the post and a polished contactsurface on which rests and turns a similar centrally apertured upperplateor disk 16. `The disk 16 is in turn rigidly secured to the bottomwire support or plate member 17 ofthe frame of the aerial as indicatedby the screws 18, said member 17 being preferably of Bakelite or thelike lThe frame also includes an upper wire support or plate member 19moiuited on the upper ends of upright corner rods 20 which are rigidlyconnected to the top and bottom plates or frame members 17 andv 19 inany suitable manner as by means of screws 21 passingthrough the platesand intov the ends of the rods 20, thusv rigidly mounting said parts inparallel relation.

The winding or wire of the loop is desig- PAIEN OFFICE the wiresarranged to extend in spaced relationship, or wound, wholly about theperipheries of the top and bottom plates andthroughout the sides or areaof the same and embodies a series of coils.

One end of the wire is indicated at 23, at which point it is anchoredt'o one of the plates or end members of the frame, preferably the bottommember'l 17, and extended through a corner opening, slot, or otherwire-receiving, or guiding and retaining-means of a spaced series 24extending entirely around the edges of the plates 17 and 19, asindicated in the drawings and particularly in Figs. 1, 3, and 4.

The wire is then extended lengthwise of the frame to the upper member 19through the corner opening` or wire-guiding means thereof, thendiagonally across to the iirst opening on the adjacent side,r.then downthrough the corresponding opening in the bottom member 17, after whichthey operationV 'of winding is repeated, the coils extending Vcoilyor'windingis designated 25 and is preterably anchored beneath thebottom plate 17 at the corner diagonally opposite theVv corner where theend 23 is located, t iese ends being, adapted for connection with thereceiving set and ground in the usual way. v l

An intermediate lead 26 is connected to one of the coils or loops of thewinding22, inter-rv mediately thereof when it is not desired to employthe entire winding of theaeriall and less inductance is required. Italso will-be notdfrom Figs. 2 and 3 of the drawings that the cent-ralloops of the Winding at the bottom are i preferably extended between theplate or Jframe member 17 and the disk 16 to' prevent interference withthe bea-ring; surfaces.` Iii is'also preferable to provide aniupright'or bridge piece 27 on the upper #trame member or plate 19extending from diago-v nally opposite corners vtransversely' orsubstantially at right angles to the eXtent'of the coils or loops of theVwinding 22, so Athat the latterA will cross or intersect this bridgepiece at right angles The bridge piece is preterably of'triangularshapev and is suitably securedy Vin'position vertically on the'plate 19with its apex at 1the center-'andy has wire guides 28 in-theI form ofopenings, grooves, -or slots', orthe purpose of receiving the wirestherein asthey are extendedy or bridged from one-'side oftheframe'tothe-other'in the form ota pyramid at the top ot the-trame, thus givinggreaterlength of coil with greater indu'ctance without materiallyincreasing the size, as well as adding to' vthe attractiveness andappearance ofthe aerial.

Itiis tobe understood ythat the guide means 24:" may be vsimpleopenings, slots, grooves, or other means, for receiving thewind-ing.' In Fig. 9 one ot the iframe members isfshotvn provided withopenings 29 'having communieating slots-.30 preferably inclined totheedge of the frame member and providing an entranceopening into whichthe wire-may be readily passed 'without' the necessity7A of threadingthe entire length of "the wire through holes and thus facilitatinoproduction. The slots arranged as shown', facilitate the entrance of thewires into the openings or guiding means and displacement-'of the wire Yis prevented, which is especially due to theinclined entrance portionsresisting upward pull or any tendency to displace the wire out- Wa-rdlyatright angles to the adjacent edge of the frame member Vand by reasonof the overhang-ing portions 3l.

In Figs'. l() and ll of thek drawings, a differ VVent-guiding means isshown in which the rfam'einember is provided witlrnotches 32 rection-alactionzfas a .broadcast receiver, suitable means are provided, such asbyengraving the lower Bakelite wire supp-ort 217,201? providing thesaine 'with a compass as'` indicated-at 35; v In the event that-theAdirections' are indicatedK on the part '17, 4an iarrovv` or pin Btl-isinserted in or mounted on=the pivot' pin or post to cooperatewiththefdirection narks' to fshow'v the f direction f l which:the loop is pointedx 'or t-helcompass may be mounted on the pin vas'showniatfl inFig. 2 ofthedrawingsgland `the' arrow .oi-ffpointerfpco-zoperateswith the dial orldirection Lmarlsf; the pointer or needle37-:be1ng 'of ther usual magnetic type :wheniemployed ineo'nnectionwiththe;compass.l Obviously I do? notdesire to be limi-tedx to f anyparticular: iconstruction ot direction' indicator,V and it isi alsosobvi'oiis that the same may be arranged otherwise than on.- the-base,'whether in'fth'e form of a compass or not;'= Y

In Figs; -5, '6,7,=and8 ofthe drawings, modificationsare shown plan.Theitram'e 39 in Fig. 5 -is shown. circulan with the: bridge piece 40'extending'ldiainetricallyg and .the winding 4.11 withl 'the coilsthereof disposedfas chords. oit-an arc' with the/exception' ofthe :7;

end coils-whichare notarranged parallel to the others at* the top: andbottom but are arranged substantially as shown in l. In Fig.l 61 thetrainee-22 is otelliptieahoroval shape in fplan 'with fthe-Jbridge'piiece .anand i:

the winding 44 arranged the samevrelation as 1n Figs. 1 andf'. In Fig.I7 the iframe/45 is ot poly-sided form. andas shown hexagonal vin plainwithla bridgefpiecelt extendinrgsubstantiarlly diana'etricallybetweentwo angular portions or across between two opposite cor.- nersand the 1winding 1.71 is disposedy atright angles' thereto. i. In Fig'the frfaineilS' is oi' triangular form in plan; in wh'ichuthe bridgepie-Ce is designated at LI9 or may beom'itted entirely, while they'winding is designated at 50. In any 'otthese` arrangements', the loopsare'close together and', irrespectiveof the geometrical shape, Vtheaerial willaccommodate a greaterlength ofvvire than has been'pos; siblewithother types of aerials, especially ,thosev having open sides or'fields.v For this reason, greater indu'ctance is 'possible than withother-loopsot the saine size,fowing to its being enclosed by a windingon-alfl sides-m.

While I have shown and described my invention in a preferred form, Iamaware that various modifications and changes may be made thereinWithout departing from the principles of the invention, the scope ofwhich is to be determined from the appended f v claims. n

I claim as my invention: r

1. A loop aerial comprising a frame including top and bottom membersspaced apart a distance greater than anydimension of the members, means`connecting said members to each other, a bridge piece on one of saidmembers, and Wires coiled around the frame and bridge piece'inengagementvvith` the members and bridge piece, said` Wires Whollyenclosing the area of theframe and having leads extending therefrom.

2. A loop aerial comprising a frame having top and bottom membersspacedapart a distance Which is a multiple of any dimension of either ofsaid members, connections between said plates forming uprights bracingthe same,a bridge piece on the top member, and Wires coiled around theframe diagonally to progressively increase and decrease in size from acentral point and detachably engaging the edges of the members and thebridge piece, the Wires being arranged to extend in equally spacedrelationship to Wholly cover the area of the frame.

3. A loop aerial comprising a base having a pivot post, a framecomprising connected top and bottom members mounted to turn on the post,a bridge piece on the top member, said members and bridge piece havingslots, a Winding comprising a continuous Wire removably mounted in saidslots and forming coils progressively increasing in vsize from one sideof the frame to an intermediate point and progressively decreasing insize from said intermediate point to the otherside to A form asubstantially closed loop land field.

4. A loop aerial comprising a rotatable frame including top and bottomplates spaced apart a distance greater than any dimension 0f the plates,means connecting said plates to each other, a bridge piece on one ofsaid (plates, and wires coiled about the frame and bridge pieceangularly with respect to the edges of the plates and in engagement withthe platesand bridge piece, said Wires Wholly enclosing the area of theframe and having leads extending therefrom. Y

ALBERT (t HARMS.

